On Unsteady Wave Pattern Analysis of Ships Advancing in Waves

An unsteady wave pattern analysis proposed by Ohkusu is one of the useful methods for investigating the mechanism between hull shape and added wave resistance and also for the validation of numerical methods from the point of view of the wave pattern that indicates the pressure distribution over the free surface. In this paper, a method to improve the accuracy of the measured diffraction wave is proposed by considering the interaction effect between the steady wave field and the incident wave that have been ignored in the original method proposed by Ohkusu.Experiments using a modified Wigley model are carried out to obtain the unsteady waves and the method we propose in this paper is applied to the diffraction waves. Results are compared with those obtained by the original method and discussed. The paper also shows the hydrodynamic forces and motions obtained through the experiments comparing with several numerical methods.